Metal wall studs are commonly used in the construction trade for framing walls and other structures. The studs are installed at spaced intervals to provide a framework for installation of drywall panels and the like.
Various track systems are known in the prior art for supporting wall studs at the desired location. Such systems typically comprise an upper track secured to the ceiling and a lower track secured to the floor in alignment with the upper track. Each wall stud is positioned between the upper and lower tracks and secured in place. In the case of “slip track” systems, the wall studs may be cut to a length less than the overall vertical distance between the upper and lower tracks. This permits some movement of the upper track relative to the lower track after installation of the wall studs. Slip track systems can thus accommodate deflection in the ceiling position relative to the wall and floor, for example due to changes in applied loads or temperature fluctuations. In some prior art systems an outer track and a movable inner track are provided to achieve the slip track functionality.
In conventional wall construction systems each stud is secured to the upper and lower tracks with fasteners, such as metal screws. This typically requires installers to use a ladder and a screw gun to secure the upper end of each stud to the upper track and building frame. The lower end of each stud is secured to the lower track in a similar manner. In some cases inexperienced tradesmen may install the studs at incorrect track locations, resulting in inconsistent spacing between the studs or off-vertical positioning. In such cases it is time-consuming and labour-intensive to remove the fasteners from the tracks and reinstall the wall studs in the correct orientation.
Some fastener-less stud alignment systems are known in the prior art where wall studs are held in place with clips or tabs formed in the tracks rather than by separate fasteners. Such systems avoid the need for screw guns or other tools for driving fasteners. However, in some cases the track clips are not designed to receive standard wall studs and custom studs must be used. In other cases studs cannot be easily extracted from the clips after installation, particularly in the case of heavier gauge studs.
U.S. Pat. No. 6,647,691, Becker et al., exemplifies the prior art in this field. Becker describes a track arrangement for supporting wall studs where the studs are held in place in the tracks with opposed clips. Each clip consists of a portion of track sidewall bent inwardly to form a cam surface and a stud ridge receiver. The studs may or may not be bottomed-out in the tracks depending on whether or not the wall is load bearing.
One drawback of the Becker track arrangement is that, once installed, the wall studs cannot be easily decoupled from the tracks. Rather, significant force would be required to extract the stud side flanges from the track clips. Also, the Becker arrangement requires that each stud be inserted within the upper and lower tracks in the same orientation, i.e. with stud side flanges projecting in one direction only.
The need has therefore arisen for a more versatile slip track assembly which permits simple removal and reinstallation of wall studs without the use of separate fasteners.